list_plans

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations provided, the description carries the full burden. It discloses that no authentication is required, which is useful behavioral context. However, it lacks details on rate limits, error handling, response format, or whether this is a read-only operation (implied by 'browse' but not explicit). The description adds some value but leaves gaps for a tool with no annotations.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is efficiently structured in three sentences: purpose definition, plan details, and authentication note. Each sentence adds value without redundancy, making it easy to parse and front-loaded with key information.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given no annotations and no output schema, the description provides basic context (purpose, authentication) but lacks details on behavioral traits like pagination behavior, return format, or error conditions. For a simple list tool with 2 parameters, it's minimally adequate but could be more complete to compensate for missing structured data.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so the schema fully documents the two parameters (limit and offset). The description doesn't add any parameter-specific information beyond what's in the schema, such as default values or usage tips. This meets the baseline of 3 when schema coverage is high.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the tool's purpose: 'Browse subscription plans on the402.ai' with specific details about what plans are (bundles of services at recurring prices) and what subscribing entails. It distinguishes from siblings like 'subscribe_to_plan' by focusing on browsing rather than subscribing, but doesn't explicitly differentiate from 'browse_products' or 'search_catalog' which might overlap.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description implies usage context by stating 'No authentication required,' suggesting this is a public-facing tool. However, it doesn't provide explicit guidance on when to use this versus alternatives like 'browse_products' or 'search_catalog,' nor does it mention prerequisites or exclusions beyond the authentication note.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.